RU2714568C1 - Cycloidal gear electric drive - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to drives. Planetary-lantern electric drive includes housing, stator and rotor installed in shell rigidly connected with electric drive eccentric input shaft. Input shaft has two oppositely oriented eccentric cylindrical sections, on which satellites with external teeth are installed through bearing supports. Input shaft transmits cycloidal motion to satellites, which leads to rolling of pins by satellite outer teeth, these pins are laid in inter-tooth cavities of fixed housing. Difference in number of external teeth of satellites and number of pins per 1÷3 leads to rotation of satellites about its axis. Between the satellite and its associated outlet flange there is a cross-shaped coupling which detaches from the complex motion of the satellite only rotation around the axis and transmits it to the output flange. Outlet flanges are installed in the housing on bearing supports and tightened by bars, at that one of output flanges is rigidly connected with output shaft.

EFFECT: improved reliability of the electric drive, as well as reduced dimensions.

1 cl, 2 dwg

Description

The invention relates to drive devices. The present invention can be applied in instrumentation and mechanical engineering, in particular, as a drive for links of robotic devices, and for special equipment.

A known transmission described in RU 2130140, with a large gear ratio. This transmission contains two satellites, which have external teeth and are mounted for rotation in at least two eccentric sections of the input shaft. For engagement with the wheel with internal teeth, the satellites are located between the output flanges. A cruciform coupling is located between the satellite with external teeth and the output flange related to it, which isolates only rotation about the axis from the complex movement of the satellite and transfers it to the output flange.

The disadvantage of this device is that the serial connection of the motor with the transmission increases the linear dimensions of the drive and the number of body parts, the transmission design provides increased requirements for the accuracy of manufacturing parts, which in turn increases the cost of transmission.

Known gearbox movement mechanism described in RU 74987, made in the form of a planetary gear transmission. This gearbox contains a housing with an output rotary link located on the bearings, consisting of two flanges connected into a single unit. Two opposed satellites are mounted on the bearings of the input eccentric shaft and interact with their epicycloidal teeth with lugs freely installed in the recesses of the housing. In this case, the satellites are connected to the output rotary link by means of fingers installed in its bearings, interacting with the cylindrical surfaces of the holes in the satellites. A distinctive feature of the gearbox is that a central spline hole is made in one of the flanges of the output rotary link.

The disadvantage of this device is that the serial connection of the motor with the gear increases the linear dimensions of the drive and the number of body parts. Satellites having epicycloidal teeth are very difficult to manufacture and require increased demands on the accuracy of the manufacture of teeth and holes for transmitting output torque through the fingers.

The prototype of the inventive planetary chain drive is a geared motor (gear motor) described in RU 2571313. This electric motor contains a housing in which a stator, rotor and planetary chain gear are housed. The rotor of the electric motor is the input shaft of the gearbox, at the ends of which two coaxial eccentric sections are formed. Reducer satellites are installed in these areas, while the space between the satellites is used to accommodate the stator of the electric motor.

The disadvantages of this device are that the layout of the satellites relative to the rotor increases linear dimensions, and the use of two spaced coaxial eccentric sections of the shaft leads to strong vibrations.

The objective of the present invention is to provide a planetary chain drive with high torque, a small angular play on the output shaft, a minimum linear dimension along the axis, and a line of electric drives with a gear ratio from 10 to 100 without changing the dimensions of the electric drive.

One embodiment of the present invention is shown in FIG. 1, which shows the main view of the inventive planetary gear drive in the context.

In FIG. 2 shows a view of the inventive planetary chain drive in section AA, which shows the engagement of the satellite and the pin in the housing.

1 - housing

2 - control unit

3 - stator

4 - rotor

5 - a glass

6 - eccentric input shaft,

7 - satellites,

8 - pin

9 - cross couplings,

10 - output flanges,

11 - rod

12 - output shaft

13 - a protective casing,

14 - a dividing ring,

15 - restrictive ring,

16 - holding lids,

17 - bushings

18 - cuff

19 - case cover.

According to an implementation example, the planetary-pinion electric drive comprises a housing 1 and a control unit 2 and a stator 3 mounted thereon. The rotor 4 is located outside the stator and is mounted in a glass 5, rigidly connected to the eccentric input shaft 6. The satellites 7 are mounted on bearing bearings located on two opposed eccentric cylindrical sections of the input shaft. Between the satellites there is a dividing ring 14. On the inner diameter of the housing grooves of the toothed profile are made, forming a fixed pinion wheel common to the satellites. The yokes 8 are held in the grooves and are held on both sides by restrictive rings 15. Each satellite is connected by a cross coupling 9 with a corresponding output flange 10. The output flanges are mounted on the input shaft and in the housing on bearing bearings and pulled together by rods 11 passing through through holes in satellites without touching them. The bearing bearings of the satellites are fixed by means of retaining caps 16. The input shaft with the bushings 17 mounted on it is located coaxially and sequentially with the output shaft 12, which is rigidly connected to one of the output flanges and mounted on the bearing support in the housing, of which the housing cover 19 is a part. The electric drive is closed by a protective casing 13 and a cuff 18 installed in the housing cover on the output shaft.

The proposed planetary pin drive operates as follows.

The electric drive contains an electric motor having a rotor and a stator, the windings of which are controlled by the control unit. One of the distinguishing features of the electric drive from analogues is that the electric motor has a rotor located outside the stator, and in the center there is a cavity for accommodating a planetary gear transmission. Such an electric motor provides greater torque in comparison with other engines of similar dimensions, and the placement of a planetary pinion gear inside the electric motor reduces the linear dimensions of the electric drive and reduces the total number of parts, which leads to more favorable economic characteristics.

The planetary pinion gear includes: an eccentric input shaft, satellites, pinwheel with pin, cross clutches, output flanges and bearing bearings. The use of a planetary-pinion gear allows you to lay a different gear ratio by changing the number of gears and teeth on the satellites in the production of a line of electric drives with a gear ratio from 10 to 100 and maintaining the dimensions of the electric drive.

The rotor of the electric drive is installed in a glass, which is rigidly fixed to the eccentric input shaft and informs it of the torque. On the opposite eccentric sections of the input shaft, two satellites are compactly placed, balancing each other, which avoids additional balancing. The input shaft through the bearings supports the satellites cycloidal motion. Sleeves are installed on the input shaft to limit axial displacement and mount the bearing bearings of the satellites and flanges. A spacer ring installed between the satellites prevents them from skewing.

Satellites run around the internal teeth of the housing, formed by the pins, which are laid in the grooves of the toothed profile made on the inner diameter of the housing. The yokes are stacked with the possibility of their free rotation around their axis, which ensures a decrease in friction between satellites and yokes, which in turn increases the efficiency of the drive. The restrictive rings hold the handles, limiting their axial and diametrical movement, which increases the reliability of the device as a whole. Satellites rotate around their axis due to the difference in the number of pin and teeth of the satellites by 1 ÷ 3. With one revolution of the eccentric shaft, the satellite rotates by an angle equal to the pitch of the gear profile. The peculiarity of the satellites is that they have a simplified tooth profile in the form of a truncated sprocket. This toothed profile is similar to that of chain sprockets with trimming of the outer diameter of the teeth. Thus, the manufacture of satellites is facilitated, making it possible to do without gear production.

Cross couplings isolate the torque from the cycloidal motion of the satellites and transmit it to the output flanges, on one of which the output shaft mounted in the housing on the bearing support is rigidly fixed to reduce the effects of bending moments on the planetary gear transmission. Cross couplings have a relatively simple design and a large bearing capacity, which allows you to remove the functions of torque transmission from satellites from the fingers tightening the output flanges. The use of cross couplings made it possible to reduce the dimensions of the electric drive as a whole and increase the reliability of its operation. To protect against external influences, the electric drive is closed with a protective casing and cuff.

The complete symmetry of the planetary gear transmission and the use of two opposed eccentric sections significantly reduces vibration during operation of the electric drive, since a pair of centrifugal oppositely directed forces is formed that balance each other.

This embodiment of the planetary-pinion drive has high accuracy, a small angular play on the output shaft, has compact linear dimensions, resistance to shock loads and efficiency of 80%.

The technical result of the invention is the creation of a planetary chain drive with high torque, a small angular play on the output shaft, a minimum linear dimension along the axis and a line of electric drives with a gear ratio from 10 to 100 without changing the dimensions of the electric drive.

Thus, a planetary chain-drive electric drive is declared comprising a housing, a stator, a rotor, an eccentric input shaft with two eccentric cylindrical sections, on which satellites are installed with bearing holes through holes and meshed with the spindles, a fixed sprocket made in housing, the output shaft mounted in the housing on the bearing support. A distinctive feature of the electric drive is that a control unit and a stator located inside the rotor are installed on the housing. The rotor is installed in a glass rigidly connected to the input shaft, in which the eccentric cylindrical sections are made opposite. The sprocket wheel and the sprockets laid in its grooves are common for the satellites, between which the separation ring is located. The sprockets are held by restrictive rings, and the gear profiles of the sprocket wheel and satellites have a simplified shape in the form of a truncated sprocket. In this case, each satellite is connected by a cross coupling with a corresponding output flange mounted on the input shaft and in the housing on bearing bearings. In turn, the output flanges are pulled together by rods passing through the through holes in the satellites without touching them. The output shaft is rigidly connected to one of the output flanges and is located coaxially and sequentially with the input shaft.

Claims (1)

A planetary sprocket electric drive comprising a housing, a stator, a rotor, an eccentric input shaft with two eccentric cylindrical sections, on which satellites are installed using bearing bearings, having through holes and meshed with the sprockets, a fixed sprocket made in the housing, an output shaft mounted in a housing on a bearing support, characterized in that a control unit and a stator are installed on the housing located inside the rotor installed in the glass, rigidly connected to the input the shaft, in which the eccentric cylindrical sections are made opposite, the sprocket wheel and the sprockets laid in its grooves are common for the satellites, between which the spacer ring is placed, the sprockets are held by restrictive rings, and the gear profiles of the sprocket wheel and satellites have a simplified shape in the form of a truncated asterisk, In this case, each satellite is connected by a cross coupling with a corresponding output flange mounted on the input shaft and in the housing on bearing bearings, in turn, the output flanges you interconnected rods extending through holes in the satellites without touching them, the output shaft is rigidly connected to one of the output flange and is disposed coaxially and in series with the input shaft.

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